In a wafer level lens process in which a plurality of lenses is disposed on a wafer substrate in the planar direction, it is difficult to obtain the shape accuracy or the position accuracy when the lenses are formed. Particularly, a high level may be needed in a process of laminating the wafer substrates so as to manufacture a layered lens structure. Thus, it is difficult to laminate three layers or more in a mass-production level.
Various technologies have been contrived and proposed in the wafer level lens process. For example, as the related art, there are proposed a hybrid type lens in which a lens is formed on a glass substrate and a monolithic type wafer lens which is formed only by a resin material. Further, PTL 1 proposes a method of forming a lens in a through-hole of a substrate. Further, in order to sufficiently obtain the lens holding stability, an opening cross-sectional shape is defined so as to widen a contact area between resin and a substrate (other than a tapered shape). Alternatively, there is proposed a method of forming unevenness by blasting a side wall surface as a countermeasure for ghost or flare.